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Ever seen a Gulf Fritillary butterfly laying an egg?
The Gulf Frit (Agraulis vanillae), an orangish-reddish butterfly of the family Nymphalidae, lays its eggs on its host plant, Passiflora.
When you see its silver-spangled underwings, you...

Many common street trees now growing in the interior of California are unlikely to persist in the warmer climate expected in 2099, according to research published in the July 2018 issue of the journal Urban Forestry & Urban Greening.

“Urban foresters in inland cities of California should begin reconsidering their palettes of common street trees to prepare for warmer conditions expected in 2099 due to climate change,” said the study's co-author, Igor Lacan, UC Cooperative Extension environmental horticulture advisor in the Bay Area.

Common trees in Coastal California cities appear to be better suited to withstand the 2099 climate.

Urban foresters in inland cities of California should begin reconsidering their palettes of common street trees to prepare for climate change.

Urban foresters in inland cities of California should begin reconsidering their palettes of common street trees to prepare for climate change.

“Our research shows that some trees now lining the streets of cities like Fresno, Stockton and Ukiah are likely to perform poorly in 2099,” Lacan said. “Those cities need to look at the conditions – and trees – now found in El Centro, Barstow and Fresno respectively.”

To reach these conclusions, Lacan and co-author, professor Joe McBride of UC Berkeley, used space-for-time substitution. They compared the most common street tree species in cities representing each of the 16 California climate zones with trees in cities that currently have climates that approximate the expected warmer conditions in the 16 cities 80 years from now.

For example, Eureka can expect a climate like Berkeley's today; Fresno's climate will resemble the climate of El Centro today. (Find the complete list of cities below.) The corresponding cities were determined with climate predictions from Cal-Adapt, which synthesizes California climate change scenarios to reach a consensus view of the magnitude of climatic warming.

“We used the mid-range models,” Lacan said. “It's very reasonable to say the warming predicted by the model we used is already ‘baked in,' regardless of any mitigation efforts. While we should take measures to prevent even greater warming – mostly by reducing the use of fossil fuels – this study aims to help adapt California urban forests to the warming that can be reasonably expected to occur.”

Lacan said he and McBride were surprised to find that coastal cities and their warm equivalents contain most of the same common urban tree species, while the warm equivalents of inland cities seemed to lack most and, in some cases, all of the common trees there today.

“It's really a sharp distinction,” Lacan said. “Perhaps they were lucky, but coastal cities are better positioned for the climate of 2099 than the inland cities.”

Climate change is only partly fueling the catastrophic fires in California. Fire scientists also lay blame on the tendency of land use planners to allow the construction of houses and businesses in areas where wildfires are a natural part of the ecosystem.

Last week Gov. Brown forecast a rise in the number, intensity, and cost of fires, warning of “the new normal that we will have to face," reported Martin Kuz in the Christian Science Monitor.

Wildfire experts say its not a new normal but has become normal because lawmakers have avoided prodding local officials, developers, and residents toward an approach to land use planning that restricts housing growth in fire-prone areas.

UC Cooperative Extension specialist Max Moritz

“If you want to keep communities safe, then you have to think about living differently, about where and how we build our communities,” said UC Cooperative Extension specialist Max Moritz. “But there's no bill in the legislature about that.”

Tomorrow's tinderboxes can be seen all over the Bay Area — from the new multi-million dollar dream homes packed along the edges of San Jose's Almaden Quicksilver County Park and Mount Diablo State Park to older residences, both modest and opulent, on peaks of the Santa Cruz Mountains and Oakland and Berkeley hills, reported Lisa Krieger of the Bay Area News Group. Similar growth is taking place in natural areas in other parts of the state, including the Sierra Nevada and Southern California.

An analysis by geographer Stephen Strader of Villanova University, published this spring in the journal Natural Hazards, found a 1,000 percent increase in the number of western U.S. homes at risk from wildfire over the past 70 years — from about 607,000 in 1940 to 6.7 million in 2010.

Housing near wildlands makes it harder to do controlled burns — one of the most effective fire suppression techniques — because of smoke concerns. Until the 1970s, fire suppression tended to minimize fire spread.

“If homes are sprinkled through the landscape, you take that key tool off the table,” Moritz said.

And as people develop rural areas, they're also more likely to ignite fires. In early California history, lightning was the major cause of wildfires. Now humans are the dominant cause of fires, from downed power lines, smoking, sparks from equipment and more.

“Now is the time to do smarter, stronger land use planning,” Moritz said, “so our future communities are not as vulnerable.”.

Sometimes they barely notice you.
Such was the case of a yellow-faced bumble bee, Bombus vosnesenskii, spotted on our Mexican sunflower (Tithonia).
If a picture is worth a thousand words, what is a bee worth?
Priceless.
If you want to learn more...

Many common street trees now growing in the interior of California are unlikely to persist in the warmer climate expected in 2099, according to research published in the July 2018 issue of the journal Urban Forestry & Urban Greening.

“Urban foresters in inland cities of California should begin reconsidering their palettes of common street trees to prepare for warmer conditions expected in 2099 due to climate change,” said the study's co-author, Igor Lacan, UC Cooperative Extension environmental horticulture advisor in the Bay Area.

Common trees in Coastal California cities appear to be better suited to withstand the 2099 climate.

Urban foresters in inland cities of California should begin reconsidering their palettes of common street trees to prepare for climate change.

“Our research shows that some trees now lining the streets of cities like Fresno, Stockton and Ukiah are likely to perform poorly in 2099,” Lacan said. “Those cities need to look at the conditions – and trees – now found in El Centro, Barstow and Fresno respectively.”

To reach these conclusions, Lacan and co-author, professor Joe McBride of UC Berkeley, used space-for-time substitution. They compared the most common street tree species in cities representing each of the 16 California climate zones with trees in cities that currently have climates that approximate the expected warmer conditions in the 16 cities 80 years from now.

For example, Eureka can expect a climate like Berkeley's today; Fresno's climate will resemble the climate of El Centro today. (Find the complete list of cities below.) The corresponding cities were determined with climate predictions from Cal-Adapt, which synthesizes California climate change scenarios to reach a consensus view of the magnitude of climatic warming.

“We used the mid-range models,” Lacan said. “It's very reasonable to say the warming predicted by the model we used is already ‘baked in,' regardless of any mitigation efforts. While we should take measures to prevent even greater warming – mostly by reducing the use of fossil fuels – this study aims to help adapt California urban forests to the warming that can be reasonably expected to occur.”

Lacan said he and McBride were surprised to find that coastal cities and their warm equivalents contain most of the same common urban tree species, while the warm equivalents of inland cities seemed to lack most and, in some cases, all of the common trees there today.

“It's really a sharp distinction,” Lacan said. “Perhaps they were lucky, but coastal cities are better positioned for the climate of 2099 than the inland cities.”